• Horticultural Science & Technology
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• v.17 no.3
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• pp.333-336
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• 1999

Current season's shoots on 2-year-old branches of 'Fuji' and 'Jonagold' apple trees were heading back pruned to 5 leaves from early May to mid July at about 12-day intervals. The summer heading back pruning induced regrowth on the pruned shoots with different responses between the two cultivars. Generally, greater regrowth occurred on the pruned shoots of 'Fuji' trees than on those of 'Jonagold', irrespective of the time of the heading cut. The shoots of 'Fuji' trees pruned in late May or in June exhibited greater regrowth compared with those pruned in early May or in July, whereas the summer heading back pruning in June resulted in the greatest regrowth for 'Jonagold'. The heading cut induced terminal flower bud formation on the pruned shoots, the percentage of which was higher in 'Fuji' than in 'Jonagold'. The highest percentages of terminal flower bud formation for 'Fuji' and 'Jonagold' were obtained with the heading cut in late May and in mid June, respectively. Percent flowering of the buds was similar in both cultivars, but percent fruit set was slightly higher in 'Fuji' than in 'Jonagold'. The time of the heading cut did not affect percent fruit set in both cultivars. Our results demonstrate that summer heading back pruning of current season's shoots induces regrowth and terminal flower bud formation therefrom when done at appropriate time, but the specific responses to the heading cut are cultivardependent.

• Korean Journal of Environmental Agriculture
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• v.24 no.4
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• pp.391-397
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• 2005

This study was carried out to examine the allelopathic effect of the aqueous extract of Hypochaeris radicata L. on growth of three gramineous forage crops, tall fescue, perennial ryegrass and italian ryegrass. The result on relative elongation ration (RER) of gramineous forage crops treated with the aqueous extract of Hypochaeris radicata L. and the change of quantity generally indicated the inhibitory effect. The inhibitory effect was increased as its concentration was increased. As a result, it is ascertained that the aqueous extract of Hypochaeris radicata L. has allelopathy effect. According to the chemical experiment of the allelochemical substances in Hypochaeris radicata L. by HPLC, there are the differences at each part of plants. However, it is ascertained that there are eleven phenolic compounds, ${\rho}-hydroxybenzoic$ acid, chlorogenic acid, catechin, caffeic acid, syringic acid, salicylic acid, ${\rho}-coumaric$ acid, ferulic acid, hesperidin, trans-cinnamic acid and naringenin. Especially three phenolic acids such as caffeic acid, ferulic acid and naringenin were detected from all part of the plant.

• Journal of Sericultural and Entomological Science
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• v.4
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• pp.27-31
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• 1965

The aim of this work was to investigate how the mulberry shoots grew well when the mulberry branches were cut down, in hight, 1/3, $\frac{1}{2}$ and 2/3 of them, respectively, just before the Spring budding. The results obtained are as follows: 1. The rate of un-sprouted buds decreased sharply down as much as half of the control if the mulberry branches were cut off. The treatment, 1/3, was best one of various cut down sizes and the un-sprouted buds concentrated on the lower parts of the branches. 2. Even though the branches were cut down, at first it seemed flat to accelerate the sprouting of buds, but rather to have a tendency to become late. The speed of leaf growth, however, became faster after the sprouting. It took 7~9 days from the beginning of buddings to the 5th full grown leaf, and.7 days for the shortest one in the treatment, 2/3, when compared with 16 days of the control. 3. If the branches were cut down, the growth of the new sprouts was accelerated. For 45 days (on 5th of May to on 10th of June), therefore. the shoots had grown up to 1.6～2.5 times of the control, 34cm long. The shoots of which the branches were cut down at 2/3 of them were longest (83cm). Furthermore. the speed of shoot growth of cut-down branches was faster than that of the control. 4. In the increased rate of the number of the mulberry leaves, there was not significant difference between the control and the treatments. 5. The total amount of shoot growth showed considerably much more in the treatments than in the control. The successing growing shoots of treatment, 2/3 were little in a number but longest per one shoot in mean shoot length. 6. It seems to be much available that we may cut down branches at 2/3 of them in order to get the scions for the cutting as soon as possible.

• Journal of Korean Society of Forest Science
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• v.103 no.2
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• pp.175-181
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• 2014

This study was conducted to evaluate stand density-specific and generalized allometric equations, and biomass expansion factors (BEFs) for two stand densities (high density of 47-year-old: $667tree{\cdot}ha^{-1}$; low density of 49-year-old: $267tree{\cdot}ha^{-1}$) of Cryptomeria japonica plantations in Namhae-gun, located in the southern Korea. Biomass in each tree component, i.e. foliage, branch, and stem, was quantified by destructive tree harvesting. Allometric regression equations of each tree component were significant (P<0.05) with diameter at breast height (DBH) accounting for 80-96% of the variation except for branch biomass in high density or foliage and cone biomass in low density. Generalized allometric equations can be used to estimate the biomass of C. japonica plantations because the slopes of allometric equations were not significantly different by the stand density. The biomass expansion factors (BEFs) were significantly lower in the high stand density (1.33) than in the low stand density (1.50). The results indicate that BEFs were affected by different stand density, while allometric equations were little related to the stand density.

• Journal of Korea Foresty Energy
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• v.23 no.2
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• pp.9-20
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• 2004

Growth and nutrients of Xinjiang poplar (Populus alba var. pyramidalis) seedlings treated with fertilizers and soil amendments were examined in nursery and windbreak at Dengkou after 6 months of treatments in Inner Mongolia, China. Soil water content was $10\%$ higher than that at most soils in desert. Height and diameter growth and foliar nitrogen (N) concentration were higher at N and nitrogen plus phosphorus (N+P) fertilizer treatments than other treatments. However, there were no differences in foliar P concentration among treatments in windbreak and foliar P concentration was higher at control than at other treatments in nursery. Yuho treatment increased height and diameter growth. Nitrogen appeared an influenciug factor for early growth of Xinjiang poplar, and P had a minor affect on growth. More long-time studies were needed to elucidate the effects of fertilizers and soil amendments on growth and nutrients of Xinjiang poplar.

• Journal of Korean Society of Forest Science
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• v.87 no.4
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• pp.611-619
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• 1998

This study was carried out to examine the effects of soil acidification on growth and nutrient status of 2 - year - old Pious densiflora Sieb. et Zucc. seedlings grown for 120 days in brown forest soils acidified with $H_2SO_4$ solution with or without leaching rations from the soil. The concentrations of A1 in the acidified soils increased with increasing amount of $H^+$ added to the soil. The total dry weight of the seedlings was decreased by the addition of the $H_2SO_4$ solution. The increase of Al concentration in the belowground part resulted from the decreased concentration of essential mineral elements such as Ca and Mg in the aboveground part. In addition, a strong positive correlation(r=0.96, p<0.001) was observed between the dry weight of the seedlings and the molar (Ca+Mg+K)/A1 ratio of the soil solution. When the molar (Ca+Mg+K)/Al ratio was approximately 7.0, the dry weight of the seedlings began to decrease compared with that of the seedlings in the control treatment. The seedlings with the molar (Ca+Mg+K)/Al ratio of 1.0 resulted from approximately 40% growth reduction compared with the control value. The results suggest that the molar (Ca+Mg+K)/Al ratio of the soil solution may be a useful indicator for assessing the critical load of acid deposition.

• Journal of Korean Society of Forest Science
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• v.101 no.4
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• pp.613-618
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• 2012

The 5-year-old seedlings and emblings which regenerated from somatic embryos were compared to the height, DBH, foliar characteristics, content of chlorophyll (chlorophyll a, b and total chlorophyll), carotenoid and leaf microstructure in Liriodendron tulipifera. In comparison of height and DBH (diameter at breast height), no significant differences were found in height (seedling, 3.8 m; embling, 3.87 m) and DBH (seedling, 12.09 cm; embling, 12.53 cm). The emblings and seedlings were similar in values of length (seedling, 108.11 mm, embling, 113.59 mm), width (seedling, 149.1 mm; embling, 167.71 mm), surface area (seedling, $119.92mm^2$; embling, $164.43mm^2$), fresh weight (seedling, 2.1 g; embling, 2.62 g) of leaf, and length (seedling, 81.49 mm; embling, 98.41 mm) and thickness (seedling, 1.66 mm; embling, 1.98 mm) of petiole. In case of chlorophyll content in the leaves, the chlorophyll a (seedlings, $11.2{\mu}g/g$; emblings, $13.2{\mu}g/g$), b (seedlings, $4.8{\mu}g/g$; emblings, $5.4{\mu}g/g$) and total content were higher in emblings ($930.2{\mu}g/g$) than seedlings ($800.1{\mu}g/g$), however, content of carotenoid (seedlings, $260.3{\mu}g/g$; embling, $265.2{\mu}g/g$) showed similar in both plants. Leaves of emblings had a similar pattern of histological structure (palisade or sponge parenchyma) to that of seedlings leaves. Therefore, the results showed that there were no remarkable growth differences when compared with 5-year-emblings and seedlings of yellow poplar.

• Asian Journal of Turfgrass Science
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• v.26 no.1
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• pp.24-34
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• 2012

The study was carried out to investigate the effects of polymer, calcium, perlite and chitosan on the growth of perennial ryegrass (Lolium perenne L., PR) and to provide a basic information needed for their practical application when establishing garden, parks, athletic field and golf courses with these materials. A total of 24 treatment combinations were applied in the study. Treatments were made of water-swelling polymer (WSP), calcium, perlite and chitosan mixed in soil organic amendment (SOA). Germination rate, turfgrass coverage, turfgrass density and top growth were evaluated in PR under greenhouse conditions. Significant differences were observed for these growth characteristics among the treatments. Turfgrass density and plant height, evaluated on a weekly basis, varied with time after seeding. A proper mixing rate of WSP was considered to be lower 3% for the growth of PR with an exception of being below 6% for turfgrass density. Germination rate and early survival capacity were greatly influenced by calcium and chitosan among the elements of calcium, perlite, and chitosan. But there was little effect by perlite. Calcium and chitosan were most effective one for turfgrass density and coverage, respectively. Top leaf-growth was influenced by all three elements, but the greatest effect was highly linked with calcium. Chitosan was very effective in early germination and vertical leaf growth, as compared with the others. Future studies are required for measuring the effect of WSP, calcium, perlite and chitosan on the turf growth characteristics in root zone mixtures of sand+SOA before a practical field use.

• Journal of Bio-Environment Control
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• v.23 no.2
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• pp.88-94
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• 2014

This study was carried out to survey the early growth characteristics of Ligularia fischeri, plants of half-shaded grounds, primarily used as functional wild edible greens and examine its shading treatment to transplant seedling. The shading treatment was regulated with the shading level(full sunlight, 35%, 50%, 75%, and 95% of full sunlight). According to the experiment, the height was the highest under 75% of shading (17.3 cm), and root diameter was the highest under full sunlight (2.13 mm). It was found that fresh weight (leaf, shoot, root and whole) was the highest (1.784 g, 1.330 g, 0.791 g, 3.905 g respectively ) under 50% of shading. In case of dry weight, leaf, shoot and whole dry weight were surveyed the highest under 35% of shading, and root dry weight was the highest under full sunlight. It was found that S/R ratio and moisture contents (leaf, shoot, root and whole) were the highest under 95% of shading. Leaf area was the highest under 50% of shading ($39.3cm^2$) and the higher shading level, the higher SLA and LAR. It was surveyed that the higher shading level, the thinner leaf thickness. In case of root characteristics, it was showed that the relatively high height growth under 35%~75% of shading, excepting 95% of shading. As a result of surveying the whole experiment, it is concluded that the early growth of L. fischeri is more effective in producing it under 50% of shading.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.1
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• pp.52-56
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• 1985

For the fundamental studies of radiation breeding in edible marine algae, the biological effects on conchospores of Porphyra species by gamma-irradiation were examined. Two varieties, Keun-cham-gim (Porphyra tenera Kjell. form tamatsuensis Miura) and Saga No.5, were chosen for this study, and their conchospores after r-irradiation($5.0{\sim}20.0$ KR) were cultured for 50 days. The results obtained were summarized as follows. 1. Gamma-irradiation in less than the dose of 20KR did not affect germination of conchospores, and almost all spores grew into two cells germ in 24 hours after irradiation, but withering germs were gradually increased in number according to higher exposure within 5 days old culture. 2. High irradiation caused the induction of giant cells, abnormal useless growth of hold-fast, lumpish thalli and callus-like lumpy tissues. 3. The liberation of neutral spores from young germs and carpospores from mature thalli were observed on the frond exposed at $10{\sim}20$ KR irradiation. All spores were normal in division and its size. 4. The best irradiation effect on growth of Keun-cham-gim was observed at 10 KR dose, whose growth-rates were $140\%$ in wet weight and $108\%$ in mean frond area, but only $48\%$ was recorded in wet weight at 20 KR exposure. Saga No.5 were in contrast with Keun-cham-gim, and their most growth-rate was $400\%$ in wet weight ($258\%$ in frond area) at 10 KR irradiation and the worst was $20\%$ at the dose of 20 KR. 5. The withering phenomenon to death by treatment of gamma-ray presented substantial difference between two varieties. Survival rate compared with control in Keun-cham-gim was $70.7\%$ at 20 KR, but that in Saga No.5 recorded $47.0\%$ at same dose. 6. Synthesizing the results of high and low r-irradiation, it was suggested tat high r-irradiation in more than 5.0 KR inhibited conspicuously the growth of germs derived from conchospores, and about half of them withered at 15.0 KR dose or more.